The colour of cider arises through the oxidation of polyphenols in the juice. It can be regulated by the addition of sulphite. If the latter is added immediately after pressing, then nearly all colour development is suppressed due to binding of sulphite to the quinoidal forms of the polyphenolics. If SO2 is added later, there is less reduction of colour because the quinones have become more intimately cross-linked. The colour decreases during fermentation because of the reducing nature of yeast.
Maillard browning reactions can occur during the storage of AJC, and these coloured products cannot be dealt with by yeast.
The colour of finished cider is standardised by the addition of caramel or other permitted colorants. The colour is removed from speciality products like white ciders by the action of adsorbents such as activated carbon.
The traditional high bitterness and astringency of ciders originate with the procyanidins. Procyanidins with a degree of polymerisation (DP) 2-4 are bitter and are referred to as 'hard tannins'. Those with a DP of 5-7 are astringent ('soft tannins'). The relative delivery of bitterness and astringency depends both on the apple cultivar and on how the apples are processed. Oxidised polyphenols adsorb (become tanned) onto the apple pulp and this suppresses both astringency and bitterness. If oxidation occurs in the absence of the pulp, then there is a relative transition from bitterness to astringency as the units polymerise. Alcohol tends to enhance bitterness but suppresses astringency.
As in the case of beer and wine, the yeast produces a range of volatile components (e.g. esters), and key variables are yeast strain, fermentation temperature, and the clarity and nutrient composition of the fermentation feedstock. Higher quality apple cultivars tend to give juice containing lower levels of assimilable nitrogen, and the attendant slower fermentation rates may be associated with enhanced flavour delivery. For instance, levels of 2-phenylethanol may be increased. Cloudy juices will ferment to give increased levels of fusel oils.
There are several non-volatile glycosidic complexes in apples that are hydrolysed by endogenous glycosidases when the fruit is disrupted. The mal-olactic fermentation results in the production of diacetyl which can afford a desirable buttery note to some ciders.
Spicy and phenolic notes arise from ethylphenol and ethyl catechol that come from phenolic acid precursors (Fig. 5.4). These are major contributors to the bittersweet flavours of well-made traditional ciders. However, at high levels, they give characters reminiscent of barnyards, possibly due to the slow growth of Brettanomyces in storage.
A listing of volatile components present in cider is offered in Table 5.5.
Was this article helpful?
You may be forgiven for thinking that these passed down secrets had gone for good, washed away with time and the modern age, But they're not. You can now own three of the best traditional did you know style reports that were much loved by our parents and grandparents. And they were pretty smart too because not only will these reports save you time and money but they'll also help you eliminate some of the scourges of modern day living such as harmful chemical usage in the home.